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团队反思与团队资源开发、利用及团队结果的关系:一项元分析
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作者 尹奎 迟志康 +2 位作者 董念念 李培凯 赵景 《心理科学进展》 CSCD 北大核心 2024年第2期228-245,共18页
基于95篇文献的96个独立研究(总样本量N=9052),对团队反思与团队资源开发、团队资源利用及团队结果(团队任务绩效、团队创造力、团队创新绩效)的关系进行了元分析,检验了国家文化(权力距离、集体主义、阳刚主义、长期取向)的调节作用,... 基于95篇文献的96个独立研究(总样本量N=9052),对团队反思与团队资源开发、团队资源利用及团队结果(团队任务绩效、团队创造力、团队创新绩效)的关系进行了元分析,检验了国家文化(权力距离、集体主义、阳刚主义、长期取向)的调节作用,探究了团队资源开发、团队资源利用在团队反思与团队结果间的中介效应。结果表明:(1)团队反思与团队资源开发、团队资源利用、团队任务绩效、团队创造力、团队创新绩效存在中等程度以上的正相关关系。(2)权力距离正向调节团队反思与团队资源利用、团队任务绩效的关系,集体主义正向调节团队反思与团队资源利用、团队任务绩效、团队创新绩效的关系,阳刚主义正向调节团队反思与团队资源利用的关系,长期取向正向调节团队反思与团队任务绩效的关系。(3)团队资源开发和团队资源利用中介了团队反思与团队结果的关系。相较团队资源开发,团队资源利用在团队反思与团队任务绩效间的中介作用更强;相较团队资源利用,团队资源开发在团队反思与团队创造力之间的中介作用更强;团队资源开发、团队资源利用在团队反思与团队创新绩效之间的中介作用不存在显著差异。研究结果有助于理解团队反思与团队资源开发、利用和团队结果的关系及跨文化差异,并为实践中的团队反思提供参考。 展开更多
关键词 团队反思 元分析 团队资源开发 团队资源利用 团队结果 AMO理论
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Impact of an oligosaccharide-based polymer on the metabolic profiles and microbial ecology of weanling pigs experimentally infected with a pathogenic E.coli
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作者 Kwangwook Kim Cynthia Jinno +4 位作者 Xunde Li David Bravo Eric Cox Peng Ji Yanhong Liu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期749-764,共16页
Background Our previous study has reported that supplementation of oligosaccharide-based polymer enhances gut health and disease resistance of pigs infected with enterotoxigenic E.coli(ETEC)F18 in a manner similar to ... Background Our previous study has reported that supplementation of oligosaccharide-based polymer enhances gut health and disease resistance of pigs infected with enterotoxigenic E.coli(ETEC)F18 in a manner similar to carbadox.The objective of this study was to investigate the impacts of oligosaccharide-based polymer or antibiotic on the host metabolic profiles and colon microbiota of weaned pigs experimentally infected with ETEC F18.Results Multivariate analysis highlighted the differences in the metabolic profiles of serum and colon digesta which were predominantly found between pigs supplemented with oligosaccharide-based polymer and antibiotic.The relative abundance of metabolic markers of immune responses and nutrient metabolisms,such as amino acids and carbohydrates,were significantly differentiated between the oligosaccharide-based polymer and antibiotic groups(q<0.2 and fold change>2.0).In addition,pigs in antibiotic had a reduced(P<0.05)relative abundance of Lachnospiraceae and Lactobacillaceae,whereas had greater(P<0.05)Clostridiaceae and Streptococcaceae in the colon digesta on d 11 post-inoculation(PI)compared with d 5 PI.Conclusions The impact of oligosaccharide-based polymer on the metabolic and microbial profiles of pigs is not fully understood,and further exploration is needed.However,current research suggest that various mechanisms are involved in the enhanced disease resistance and performance in ETEC-challenged pigs by supplementing this polymer. 展开更多
关键词 CARBADOX Colon microbiota Enterotoxigenic E.coli F18 Metabolomics Oligosaccharide-based polymer Weaned pigs
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Susceptibility of dairy cows to subacute ruminal acidosis is reflected in both prepartum and postpartum bacteria as well as odd-and branched-chain fatty acids in feces 被引量:1
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作者 Hong Yang Stijn Heirbaut +4 位作者 Xiaoping Jing Nympha De Neve Leen Vandaele Jeyamalar Jeyanathan Veerle Fievez 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第1期229-243,共15页
Background:The transition period is a challenging period for high-producing dairy cattle.Cows in early lactation are considered as a group at risk of subacute ruminal acidosis(SARA).Variability in SARA susceptibility ... Background:The transition period is a challenging period for high-producing dairy cattle.Cows in early lactation are considered as a group at risk of subacute ruminal acidosis(SARA).Variability in SARA susceptibility in early lactation is hypothesized to be reflected in fecal characteristics such as fecal pH,dry matter content,volatile and odd-and branched-chain fatty acids(VFA and OBCFA,respectively),as well as fecal microbiota.This was investigated with 38 periparturient dairy cows,which were classified into four groups differing in median and mean time of reticular pH below 6 as well as area under the curve of pH below 6.Furthermore,we investigated whether fecal differences were already obvious during a period prior to the SARA risk(prepartum).Results:Variation in reticular pH during a 3-week postpartum period was not associated with differences in fecal pH and VFA concentration.In the postpartum period,the copy number of fecal bacteria and methanogens of unsusceptible(UN)cows was higher than moderately susceptible(MS)or susceptible(SU)cows,while the genera Ruminococcus and Prevotellacea_UCG-001 were proportionally less abundant in UN compared with SU cows.Nevertheless,only a minor reduction was observed in iso-BCFA proportions in fecal fatty acids of SU cows,particularly iso-C15:0and iso-C16:0,compared with UN cows.Consistent with the bacterial changes postpartum,the lower abundance of Ruminococcus was already observed in the prepartum fecal bacterial communities of UN cows,whereas Lachnospiraceae_UCG-001 was increased.Nevertheless,no differences were observed in the prepartum fecal VFA or OBCFA profiles among the groups.Prepartum fecal bacterial communities of cows were clustered into two distinct clusters with 70%of the SU cows belonging to cluster 1,in which they represented 60%of the animals.Conclusions:Inter-animal variation in postpartum SARA susceptibility was reflected in post-and prepartum fecal bacterial communities.Differences in prepartum fecal bacterial communities could alert for susceptibility to develop SARA postpartum.Our results generated knowledge on the association between fecal bacteria and SARA development which could be further explored in a prevention strategy. 展开更多
关键词 Fecal bacterial community Fecal odd-and branched-chain fatty acids Inter-animal variation Subacute ruminal acidosis
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Correlation analysis between the Aral Sea shrinkage and the Amu Darya River 被引量:1
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作者 WANG Min CHEN Xi +6 位作者 CAO Liangzhong KURBAN Alishir SHI Haiyang WU Nannan EZIZ Anwar YUAN Xiuliang Philippe DE MAEYER 《Journal of Arid Land》 SCIE CSCD 2023年第7期757-778,共22页
The shrinkage of the Aral Sea,which is closely related to the Amu Darya River,strongly affects the sustainability of the local natural ecosystem,agricultural production,and human well-being.In this study,we used the B... The shrinkage of the Aral Sea,which is closely related to the Amu Darya River,strongly affects the sustainability of the local natural ecosystem,agricultural production,and human well-being.In this study,we used the Bayesian Estimator of Abrupt change,Seasonal change,and Trend(BEAST)model to detect the historical change points in the variation of the Aral Sea and the Amu Darya River and analyse the causes of the Aral Sea shrinkage during the 1950–2016 period.Further,we applied multifractal detrend cross-correlation analysis(MF-DCCA)and quantitative analysis to investigate the responses of the Aral Sea to the runoff in the Amu Darya River,which is the main source of recharge to the Aral Sea.Our results showed that two significant trend change points in the water volume change of the Aral Sea occurred,in 1961 and 1974.Before 1961,the water volume in the Aral Sea was stable,after which it began to shrink,with a shrinkage rate fluctuating around 15.21 km3/a.After 1974,the water volume of the Aral Sea decreased substantially at a rate of up to 48.97 km3/a,which was the highest value recorded in this study.In addition,although the response of the Aral Sea's water volume to its recharge runoff demonstrated a complex non-linear relationship,the replenishment of the Aral Sea by the runoff in the lower reaches of the Amu Darya River was identified as the dominant factor affecting the Aral Sea shrinkage.Based on the scenario analyses,we concluded that it is possible to slow down the retreat of the Aral Sea and restore its ecosystem by increasing the efficiency of agricultural water use,decreasing agricultural water use in the middle and lower reaches,reducing ineffective evaporation from reservoirs and wetlands,and increasing the water coming from the lower reaches of the Amu Darya River to the 1961–1973 level.These measures would maintain and stabilise the water area and water volume of the Aral Sea in a state of ecological restoration.Therefore,this study focuses on how human consumption of recharge runoff affects the Aral Sea and provides scientific perspective on its ecological conservation and sustainable development. 展开更多
关键词 Aral Sea shrinkage recharge runoff Amu Darya River Syr Darya River multifractal detrend cross-correlation analysis(MF-DCCA) Bayesian Estimator of Abrupt change Seasonal change and Trend(BEAST) Central Asia
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Active Machine Learning for Chemical Engineers:A Bright Future Lies Ahead!
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作者 Yannick Ureel Maarten R.Dobbelaere +4 位作者 Yi Ouyang Kevin De Ras Maarten K.Sabbe Guy B.Marin Kevin M.Van Geem 《Engineering》 SCIE EI CAS CSCD 2023年第8期23-30,共8页
By combining machine learning with the design of experiments,thereby achieving so-called active machine learning,more efficient and cheaper research can be conducted.Machine learning algorithms are more flexible and a... By combining machine learning with the design of experiments,thereby achieving so-called active machine learning,more efficient and cheaper research can be conducted.Machine learning algorithms are more flexible and are better than traditional design of experiment algorithms at investigating processes spanning all length scales of chemical engineering.While active machine learning algorithms are maturing,their applications are falling behind.In this article,three types of challenges presented by active machine learning—namely,convincing the experimental researcher,the flexibility of data creation,and the robustness of active machine learning algorithms—are identified,and ways to overcome them are discussed.A bright future lies ahead for active machine learning in chemical engineering,thanks to increasing automation and more efficient algorithms that can drive novel discoveries. 展开更多
关键词 Active machine learning Active learning Bayesian optimization Chemical engineering Design of experiments
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DIC Based Strain and Damage Analysis of Large Scale Steel to Composite Adhesive Joints Subjected to Tension and Compression Loading
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作者 Pankaj R.JAISWAL Rahul Iyer KUMAR +1 位作者 Richard TRUMPER Wim DE WAELE 《China Ocean Engineering》 SCIE EI CSCD 2023年第4期588-597,共10页
This paper reports an experimental study of the mechanical response to tensile and compressive force of large scale steel to composite joints adhesively bonded with a thin layer of vinylester resin.In one specimen,the... This paper reports an experimental study of the mechanical response to tensile and compressive force of large scale steel to composite joints adhesively bonded with a thin layer of vinylester resin.In one specimen,the length of the reinforcing fibres in contact with the steel substrate has been reduced by saw cutting at both ends of the joint.This damaged specimen and four intact specimens were subjected to quasi-static tensile testing;six specimens were used for compression testing.The strain distribution at the composite surface and at the steel to hardwood connection of the specimen was monitored by digital image correlation(DIC).DIC allowed identifying the onset of damage in the tensile tested joints near the interface of the composite layer and the steel-hardwood connection.Both tensile and compression tested specimens failed due to significant peel strain concentration at the composite near the connection of steel and hardwood.The average strength of a specimen tested in compression was about 66%higher than the average strength of a specimen tested in tension.The strain concentration zone in the damaged specimen was away from the introduced saw cuts.As a result the damaged and intact tensile specimens showed the same failure strength and stiffness.All specimens failed by adhesive failure between the composite-hardwood interface. 展开更多
关键词 vinylester resin multi-material joint STRAIN DAMAGE digital image correlation.
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Tree-based ecosystem services supply and multifunctionality of church forests and their agricultural matrix near Lake Tana,Ethiopia
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作者 Ferehiwot Mequanint Tobias Fremout +7 位作者 Diederik Strubbe Alemayehu Wassie Shimelis Aynalem Enyew Adgo Jan Nyssen Amaury Frankl Luc Lens Bart Muys 《Forest Ecosystems》 SCIE CSCD 2023年第6期656-667,共12页
Ecosystem services(ES)are the connection between nature and society,and are essential for the well-being of local communities that depend on them.In Ethiopia,church forests and the surrounding agricultural matrix supp... Ecosystem services(ES)are the connection between nature and society,and are essential for the well-being of local communities that depend on them.In Ethiopia,church forests and the surrounding agricultural matrix supply numerous ES.However,the ES delivered by both land use types have not yet been assessed simultaneously.Here we surveyed both church forests and their agricultural matrices,aiming to quantify,compare and unravel the drivers underlying tree-based ES supply,density and multifunctionality.We found that almost all church forests and half of the agricultural matrices provided high ES densities.ES multifunctionality was higher in the agricultural matrices,suggesting that people deliberately conserve or plant multifunctional tree species.Furthermore,the supply of all categories of ES was positively correlated with church forest age(p-value<0.001)in the agricultural matrix,while the extent of church forest was positively correlated with the density of all categories ecosystem services score in the church forests(p-value<0.001).Our results can be used to prioritize conservation efforts at sites that provide high levels of ES supply,ES density and ES multifunctionality,and to prioritize restoration efforts at sites with low levels thereof. 展开更多
关键词 Church forest Remnant forest Provisioning service Regulating service Cultural service Multifunctionality Key informant interview Agricultural matrix
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Impact of trading hours extensions on foreign exchange volatility:intraday evidence from the Moscow exchange
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作者 Michael Frommel Eyup Kadioglu 《Financial Innovation》 2023年第1期2729-2751,共23页
Using transaction-level tick-by-tick data of same-and next-day settlement of the Russian Ruble versus the US Dollar exchange rate(RUB/USD)traded on the Moscow Exchange Market during the period 2005–2013,we analyze th... Using transaction-level tick-by-tick data of same-and next-day settlement of the Russian Ruble versus the US Dollar exchange rate(RUB/USD)traded on the Moscow Exchange Market during the period 2005–2013,we analyze the impact of trading hours extensions on volatility.During the sample period,the Moscow Exchange extended trading hours three times for the same-day settlement and two times for the next-day settlement of the RUB/USD rate.To analyze the effect of the implementations,various measures of historical and realized volatility are calculated for 5-and 15-min intraday intervals spanning a period of three months both prior to and following trading hours extensions.Besides historical volatility measures,we also examine volume and spread.We apply an autoregressive moving average-autoregressive conditional heteroscedasticity(ARMA-GARCH)model utilizing realized volatility and a trade classification rule to estimate the probability of informed trading.The extensions of trading hours cause a significant increase in both volatility and volume for further analyzing the reasons behind volatility changes.Volatility changes mostly occur after the opening of the market.The length of the extension has a significant positive effect on realized volatility.The results indicate that informed trading increased substantially after the opening for the rate of same-day settlement,whereas this is not observed for next-day settlement.Although trading hours extensions raise opportunities for more transactions and liquidity in foreign exchange markets,they may also lead to higher volatility in the market.Furthermore,this distortion is more significant at opening and midday.A potential explanation for the increased volatility mostly at the opening is that the trading hours extension attracts informed traders rather than liquidity providers. 展开更多
关键词 VOLATILITY Trading hours extension Foreign exchange market Informed trading Volume Spread Market overlap Information flow
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Inflammatory myofibroblastic tumor of the distal common bile duct:Literature review with focus on pathological examination
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作者 Fleur Cordier Anne Hoorens +2 位作者 Liesbeth Ferdinande Jo Van Dorpe David Creytens 《World Journal of Clinical Cases》 SCIE 2023年第20期4734-4739,共6页
Inflammatory myofibroblastic tumor(IMT)of the biliary tract is rare,and often difficult to diagnose or to distinguish from other tumors due to its atypical clinical presentation and nonspecific radiological features.H... Inflammatory myofibroblastic tumor(IMT)of the biliary tract is rare,and often difficult to diagnose or to distinguish from other tumors due to its atypical clinical presentation and nonspecific radiological features.Histologically,IMTs are(myo)fibroblastic neoplasms with a prominent inflammatory infiltrate.They are characterized by receptor tyrosine kinase gene rearrangements,most often involving an anaplastic lymphoma kinase(ALK)translocation.The final diagnosis of IMT depends on histopathology and immunohistochemical examination.In this manuscript,we provide a clinical and morphomolecular overview of IMT and the difficulties that may arise in using immunohistochemical and molecular techniques in diagnosing IMT. 展开更多
关键词 Inflammatory myofibroblastic tumor Fluorescence in situ hybridization Nextgeneration sequencing Mesenchymal tumors of the gastrointestinal tract
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The notion of dominant terminology in bibliometric research
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作者 Yves Fassin Ronald Rousseau 《Journal of Data and Information Science》 CSCD 2023年第4期1-7,共7页
In this opinion paper, we introduce the expressions of dominant terminology and dominant term in the quantitative studies of science in analogy to the notion of dominant design in product development and innovation.
关键词 Dominant design Dominant terminology Science of science BIBLIOMETRICS SCIENTOMETRICS
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Model Identification and Control of Electromagnetic Actuation in Continuous Casting Process With Improved Quality
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作者 Isabela Birs Cristina Muresan +1 位作者 Dana Copot Clara Ionescu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第1期203-215,共13页
This paper presents an original theoretical framework to model steel material properties in continuous casting line process. Specific properties arising from non-Newtonian dynamics are herein used to indicate the natu... This paper presents an original theoretical framework to model steel material properties in continuous casting line process. Specific properties arising from non-Newtonian dynamics are herein used to indicate the natural convergence of distributed parameter systems to fractional order transfer function models. Data driven identification from a real continuous casting line is used to identify model of the electromagnetic actuator device to control flow velocity of liquid steel. To ensure product specifications, a fractional order control is designed and validated on the system. A projection of the closed loop performance onto the quality assessment at end production line is also given in this paper. 展开更多
关键词 Electromagnetic actuator fractional order control fractional order system model non-Newtonian material
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In Vitro Synthetic Seed Production of Potato under Different Fungicide Levels and Storage Intervals
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作者 Tahira Kalsoom Touqeer Ahmed +3 位作者 Muhammad Azam Khan Mirza Hasanuzzaman Mukhtar Ahmed Stefaan P.O.Werbrouck 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第8期2429-2450,共22页
Potato propagation through tubers and seed is an inefficient way of propagation thus we propose an alternative method in this study which is in vitro propagation.Plantlets were raised from True Potato Seeds(TPS)in test... Potato propagation through tubers and seed is an inefficient way of propagation thus we propose an alternative method in this study which is in vitro propagation.Plantlets were raised from True Potato Seeds(TPS)in test tubes containing 10 mL of Murashige Skoog(MS)medium.Subculturing was done after every 21 days and after four subsequent subculturing,when there was an adequate quantity of stock material,uninodal cuttings of about 3-4 mm in length were prepared from in vitro proliferated potato plants by excising leaves of 1-2 mm on each side of the node.Prepared uninodal cuttings were cultured on 1/2 strength MS medium for root primordia development.The selected uninodal cuttings with root primordia were encapsulated with sodium alginate solution(3.5%(w/v)),mixed with 1.25%charcoal and different concentration of fungicide(thiophanate methyl,sigma)to enhance the viability percentage of synthetic seed.Furthermore,these encapsulated uninodal cuttings were subjected to different storage intervals to check maximum storage.Results showed that optimum dose for fungicide is 150 mg/L as it resulted in good viability percentage,shoot number,shoot length,rooting percentage,root number,root length and ideal for bead formation with sodium alginate.Similarly,results revealed that encapsulated uninodal cuttings can be stored at a temperature of 4℃ up to 45 days with a survival rate of 63.33%.Encapsulated uninodal cutting stored for 60 days showed a poor viability percentage of about 43.03%.It can be concluded that optimum dose of 150 mg/L with storage time of 45 days should be used to get a better outcome for synthetic potato seed production. 展开更多
关键词 Synthetic seeds potato STORAGE charcoal sodium alginate FUNGICIDE
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Frequency‐to‐spectrum mapping GAN for semisupervised hyperspectral anomaly detection
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作者 Degang Wang Lianru Gao +2 位作者 Ying Qu Xu Sun Wenzhi Liao 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第4期1258-1273,共16页
Most unsupervised or semisupervised hyperspectral anomaly detection(HAD)methods train background reconstruction models in the original spectral domain.However,due to the noise and spatial resolution limitations,there ... Most unsupervised or semisupervised hyperspectral anomaly detection(HAD)methods train background reconstruction models in the original spectral domain.However,due to the noise and spatial resolution limitations,there may be a lack of discrimination between backgrounds and anomalies.This makes it easy for the autoencoder to capture the lowlevel features shared between the two,thereby increasing the difficulty of separating anomalies from the backgrounds,which runs counter to the purpose of HAD.To this end,the authors map the original spectrums to the fractional Fourier domain(FrFD)and reformulate it as a mapping task in which restoration errors are employed to distinguish background and anomaly.This study proposes a novel frequency‐to‐spectrum mapping generative adversarial network for HAD.Specifically,the depth separable features of backgrounds and anomalies are enhanced in the FrFD.Due to the semisupervised approach,FTSGAN needs to learn the embedded features of the backgrounds,thus mapping and restoring them from the FrFD to the original spectral domain.This strategy effectively prevents the model from focussing on the numerical equivalence of input and output,and restricts the ability of FTSGAN to restore anomalies.The comparison and analysis of the experiments verify that the proposed method is competitive. 展开更多
关键词 deep learning generative adversarial network hyperspectral image neural network semisupervised learning
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Dietary resistant starch alleviates Escherichia coli-induced bone loss in meat ducks by promoting short-chain fatty acid production and inhibiting Malt1/NF-κB inflammasome activation
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作者 Huaiyong Zhang Simeng Qin +6 位作者 Xiangli Zhang Pengfei Du Yao Zhu Yanqun Huang Joris Michiels Quifeng Zeng Wen Chen 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第1期261-277,共17页
Background:Escherichia coli(E.coli)infection in humans and animals usually comes with gut dysbiosis,which is potential culprit to skeletal health,it is still unclear to whether diet interfered gut microbiome changes c... Background:Escherichia coli(E.coli)infection in humans and animals usually comes with gut dysbiosis,which is potential culprit to skeletal health,it is still unclear to whether diet interfered gut microbiome changes can be a protective strategy to bone loss development.Here,the effects of resistant starch from raw potato starch(RPS),a type of prebiotic,on E.coli-induced bone loss and gut microbial composition in meat ducks were evaluated.Results:The results showed that dietary 12%RPS treatment improved bone quality,depressed bone resorption,and attenuated the pro-inflammatory reaction in both ileum and bone marrow.Meanwhile,the 12%RPS diet also increased the abundance of Firmicutes in E.coli-treated birds,along with higher production of short-chain fatty acids(SCFAs)especially propionate and butyrate.Whereas addition ofβ-acid,an inhibitor of bacterial SCFAs production,to the drinking water of ducks fed 12%RPS diet significantly decreased SCFAs level in cecum content and eliminated RPS-induced tibial mass improvement.Further,treatment with MI-2 to abrogate mucosa-associated lymphoid tissue lymphoma translocation protein 1(Malt1)activity replicated the protective role of dietary 12%RPS in E.coli-induced bone loss including reduced the inhibition on nuclear factorκB(NF-κB)inflammasome activation,decreased bone resorption,and improved bone quality,which were correlated with comparable and higher regulatory T cells(Treg)frequency in MI-2 and 12%RPS group,respectively.Conclusions:These findings suggested that the diet with 12%RPS could alleviate E.coli-induced bone loss in meat ducks by changing the gut microbial composition and promoting concomitant SCFAs production,and consequently inhibiting Malt1/NF-κB inflammasome activation and Treg cells expansion. 展开更多
关键词 Bone loss Malt1/NF-κB signalling MICROBIOTA Resistant starch SCFAs
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Multi-criteria comparative analysis of the pressure drop on coal gangue fly-ash slurry at different parts along an L-shaped pipeline
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作者 Defeng Wang Dengwu Jiao +2 位作者 Zhanbo Cheng Qingwen Shi Helmut Mischo 《International Journal of Coal Science & Technology》 EI CAS CSCD 2023年第2期129-145,共17页
Disposing of coal gangue and fly-ash on the surface is a risky method with tremendous potential catastrophic consequences for the environment.Backfill mining is a promising practice for turning those hazardous wastes ... Disposing of coal gangue and fly-ash on the surface is a risky method with tremendous potential catastrophic consequences for the environment.Backfill mining is a promising practice for turning those hazardous wastes into functional backfill materi-als.Unfortunately,how to efficiently deliver the slurry to the desired places remains under-researched.To address this issue,the computational fluid dynamics software Fluent was used in the current study in addition to a laboratory rheological test to simulate the impact of various parameters on the evolution of pressure at a particular section of the pipeline.Furthermore,the response surface method was employed to investigate how the various components and their corresponding influencing weights interact to affect the pressure drop.This study demonstrates that the pressure drop of the slurry is highly influenced by slurry concentration,speed,and pipe diameter.While conveying speed is the main component in the bend section,pipe diameter takes over in the horizontal and vertical pipe sections. 展开更多
关键词 Coal gangue slurry Pressure drop Numerical simulation Response surface analysis
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Osteomodulin downregulation is associated with osteoarthritis development
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作者 Jérémie Zappia Qiao Tong +11 位作者 Renée Van der Cruyssen Frederique MFCornelis Cécile Lambert Tiago Pinto Coelho Juliane Grisart Erika Kague Rik JLories Marc Muller Dirk Elewaut Chrissy LHammond Christelle Sanchez Yves Henrotin 《Bone Research》 SCIE CAS CSCD 2023年第4期721-736,共16页
Abnormal subchondral bone remodeling leading to sclerosis is a main feature of osteoarthritis(OA), and osteomodulin(OMD), a proteoglycan involved in extracellular matrix mineralization, is associated with the scleroti... Abnormal subchondral bone remodeling leading to sclerosis is a main feature of osteoarthritis(OA), and osteomodulin(OMD), a proteoglycan involved in extracellular matrix mineralization, is associated with the sclerotic phenotype. However, the functions of OMD remain poorly understood, specifically in vivo. We used Omd knockout and overexpressing male mice and mutant zebrafish to study its roles in bone and cartilage metabolism and in the development of OA. The expression of Omd is deeply correlated with bone and cartilage microarchitectures affecting the bone volume and the onset of subchondral bone sclerosis and spontaneous cartilage lesions. Mechanistically, OMD binds to RANKL and inhibits osteoclastogenesis, thus controlling the balance of bone remodeling. In conclusion, OMD is a key factor in subchondral bone sclerosis associated with OA. It participates in bone and cartilage homeostasis by acting on the regulation of osteoclastogenesis. Targeting OMD may be a promising new and personalized approach for OA. 展开更多
关键词 METABOLISM CONCLUSION HOMEOSTASIS
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纤维素醚改性砂浆的研究进展 被引量:29
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作者 蹇守卫 马保国 +3 位作者 苏雷 李相国 穆松 袁龙 《硅酸盐通报》 CAS CSCD 北大核心 2011年第3期560-566,共7页
本文分析了纤维素醚的种类及其在干混砂浆的主要作用和保水性、粘度、粘结强度等性能评价方法,阐述了纤维素醚在干混砂浆中的缓凝机理、微观结构及某些特定薄层纤维素醚改性砂浆的结构形成与水化过程的关系,在此基础上,提出必须加快研... 本文分析了纤维素醚的种类及其在干混砂浆的主要作用和保水性、粘度、粘结强度等性能评价方法,阐述了纤维素醚在干混砂浆中的缓凝机理、微观结构及某些特定薄层纤维素醚改性砂浆的结构形成与水化过程的关系,在此基础上,提出必须加快研究在快速失水条件下,薄层结构中纤维素醚改性砂浆的分层水化机理及聚合物在砂浆层的空间分布规律,未来在实际应用中应充分考虑纤维素醚改性砂浆受温度变化的影响、与其它外加剂的相容性等,本研究工作将促进CE改性砂浆如外墙抹灰砂浆、腻子、勾缝砂浆等薄层砂浆的应用技术发展。 展开更多
关键词 纤维素醚 干混砂浆 机理
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合肥盆地构造演化的磷灰石裂变径迹分析 被引量:20
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作者 许长海 周祖翼 +2 位作者 P.Van Den Haute J.L.Mansy 杨风丽 《石油学报》 EI CAS CSCD 北大核心 2006年第6期5-13,共9页
磷灰石裂变径迹(AFT)分析表明,合肥盆地北部K2^1砂岩的AFT年龄为(128.2±95)Ma,围限径迹长度为(11.9±0.4)μm。其模拟热史包括4个阶段:在距今175~150Ma,冷却速率为8.92℃/Ma;在距今150~85Ma为0.99℃/Ma;... 磷灰石裂变径迹(AFT)分析表明,合肥盆地北部K2^1砂岩的AFT年龄为(128.2±95)Ma,围限径迹长度为(11.9±0.4)μm。其模拟热史包括4个阶段:在距今175~150Ma,冷却速率为8.92℃/Ma;在距今150~85Ma为0.99℃/Ma;在距今85~24Ma为-0.49℃/Ma;在距今24Ma以来为1.96℃/Ma,它们依次对应于物源区快速抬升剥露、缓慢抬升剥露以及盆地先沉降后抬升4个阶段。盆地南缘黑石渡组(K1h)的AFT年龄为(86.3±43)Ma,平均围限径迹长度为(13.6±0.2)μm。模拟热史表明,在距今135~122Ma时冷却速率为-13.60℃/Ma;在距今122~98Ma时为1.92℃/Ma;在距今98~90Ma时为6.63℃/Ma;在距今90~26Ma时为0.88℃/Ma;在距今26Ma以来为0.69℃/Ma,它们依次与沉积埋藏加热、缓慢抬升剥露、快速抬升剥露以及两次缓慢剥露5个阶段相对应。合肥盆地的演化先后受到大别造山带与郯庐断裂带构造活动的控制:即盆地挤压阶段(早侏罗世至距今150Ma)受控于大别山晚造山期挤压环境,盆地伸展断陷阶段(距今150~138Ma)受控于大别山造山根拆沉作用,盆地滑覆冲断一走滑阶段(距今138-90Ma)受控于造山带热窿伸展与郯庐断裂走滑联合作用,盆地走滑拉张阶段(距今90~25Ma)受控于郯庐断裂带走滑拉张作用,盆地挤压抬升阶段(距今25Ma以来)受控于郯庐断裂带挤压环境。 展开更多
关键词 磷灰石裂变径迹 热史模拟 构造演化 区域控制 合肥盆地
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农田土壤有机碳含量对作物产量影响的模拟研究 被引量:68
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作者 邱建军 王立刚 +3 位作者 李虎 唐华俊 Changsheng Li Eric Van Ranst 《中国农业科学》 CAS CSCD 北大核心 2009年第1期154-161,共8页
【目的】探求土壤有机碳含量对作物产量的影响,以期为保障国家粮食安全和耕地持续利用与管理提供决策依据。【方法】利用农田生态系统生物地球化学模型DNDC,针对中国东北、华北、西北、中南、华东和西南6个典型农业区域,每个区域选择各... 【目的】探求土壤有机碳含量对作物产量的影响,以期为保障国家粮食安全和耕地持续利用与管理提供决策依据。【方法】利用农田生态系统生物地球化学模型DNDC,针对中国东北、华北、西北、中南、华东和西南6个典型农业区域,每个区域选择各自典型的种植模式和现行的农田管理措施,在各自特定的土壤和气候条件下,输入并运行模型,模拟考察在其它投入条件不变的情况下,改变土壤有机碳本底值对作物产量的影响。【结果】当土壤有机碳含量(SOC)增加1g C.kg-1,东北地区玉米产量可增加176kg·hm-2;华北地区夏玉米与冬小麦轮作,产量可增加约454kg·hm-2;西北地区春玉米产量约可增加328kg·hm-2;中南地区单季水稻产量可增加约185kg·hm-2;华东地区双季稻产量可增加约266kg·hm-2;西南地区水稻与冬小麦轮作产量可增加约229kg·hm-2。【结论】在其它投入既定的条件下,全国各地区均存在通过提高耕地土壤有机碳含量来增加作物产量的潜力。保持较高水平的土壤有机碳含量对节本增效具有十分明显的作用。 展开更多
关键词 土壤有机碳 粮食产量 碳固存 DNDC模型
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Words apart:Standardizing forestry terms and definitions across European biodiversity studies
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作者 Giovanni Trentanovi Thomas Campagnaro +36 位作者 Tommaso Sitzia Francesco Chianucci Giorgio Vacchiano Christian Ammer MichałCiach Thomas ANagel Miren del Río Yoan Paillet Silvana Munzi Kris Vandekerkhove Andrés Bravo-Oviedo Andrea Cutini Ettore D'Andrea Pallieter De Smedt Inken Doerfler Dimitris Fotakis Jacob Heilmann-Clausen Jeňýk Hofmeister Jan Hošek Philippe Janssen Sebastian Kepfer-Rojas Nathalie Korboulewsky Bence Kovács Daniel Kozák Thibault Lachat Anders Mårell Radim Matula Martin Mikoláš Björn Nordén PéterÓdor x Marko Perović Elisabeth Pötzelsberger Peter Schall Miroslav Svoboda Flóra Tinya Mariana Ujházyová Sabina Burrascano 《Forest Ecosystems》 SCIE CSCD 2023年第4期459-471,共13页
Forest biodiversity studies conducted across Europe use a multitude of forestry terms,often inconsistently.This hinders the comparability across studies and makes the assessment of the impacts of forest management on ... Forest biodiversity studies conducted across Europe use a multitude of forestry terms,often inconsistently.This hinders the comparability across studies and makes the assessment of the impacts of forest management on biodiversity highly context-dependent.Recent attempts to standardize forestry and stand description terminology mostly used a top-down approach that did not account for the perspectives and approaches of forest biodiversity experts.This work aims to establish common standards for silvicultural and vegetation definitions,creating a shared conceptual framework for a consistent study on the effects of forest management on biodiversity.We have identified both strengths and weaknesses of the silvicultural and vegetation information provided in forest biodiversity studies.While quantitative data on forest biomass and dominant tree species are frequently included,information on silvicultural activities and vegetation composition is often lacking,shallow,or based on broad and heterogeneous classifications.We discuss the existing classifications and their use in European forest biodiversity studies through a novel bottom-up and top-driven review process,and ultimately propose a common framework.This will enhance the comparability of forest biodiversity studies in Europe,and puts the basis for effective implementation and monitoring of sustainable forest management policies.The standards here proposed are potentially adaptable and applicable to other geographical areas and could be extended to other forest interventions. 展开更多
关键词 Forest management Multi-taxon Terminology SILVICULTURE Data harmonization
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